And here is the latest: BQ.1.1. For the time being in France, where various subvariants of Omicron are spreading, the epidemic remains dominated by BA.5. Two “adapted” bivalent vaccines have also been available since the beginning of October for booster doses.
High immune escape
Increasingly, the Covid-19 epidemic is resulting in the coexistence of several versions of the virus, for the time being all from the Omicron variant, as shown by the successive results of flash surveys in recent months:
Highly contagious, actively circulating, and confronted with immunity acquired via vaccines or previous infections, Omicron has given rise to dozens of different sub-versions, through numerous mutations:
One of the latest, BQ.1.1, is worrying for at least one reason: its mutations are likely to lead to a very strong immune escape. As such, it can supplant the others more or less quickly. But, above all, lead to a very large number of infections, such as the first avatars of Omicron at the end of 2021 and in 2022.
A situation which, shortly before the start of winter, can be worrying: if hospitalizations have become rarer with Covid-19, a very significant spread necessarily leads to a significant quantity.
Nausea, abdominal pain… Really new symptoms?
BQ.1.1 would now weigh between 1 and 6% of cases in France, according to the rare sequencing data. The current low screening rate and the low level of sequencing prevent us from seeing things more clearly: “Today, to sequence, we are asked for 5% of the samples from a single day”, explains a biologist from the center of the France.
What about symptoms? Some fragmentary and poorly substantiated information from Thailand and the United Kingdom mentions stomach aches, diarrhea and vomiting as frequent symptoms with BQ.1.1.
So much so that serious specialists have sometimes in turn disseminated them… before backpedaling. This is the case of pediatrician Rémi Salomon, very advanced on the Covid-19 pandemic:
The arrival of the BQ.1.1 variant is not good news. It has the particularity of causing diarrhea and vomiting
Rémi Salomon, before correcting his message
Several cases of Covid-19 infected with BQ.1.1 have testified to such symptoms. Doctors report these disorders “clearly more frequent”.
But “in a context of strong circulation of different viruses, it is difficult to deduce that these not very specific symptoms are due to the sub-variant”, nuances a medical biologist.
Above all, to varying degrees, digestive problems belong from the start to the symptoms regularly observed with Covid-19: they appeared in 5 to 10% of patients infected with the Alpha or Delta variants.
Since the start of the Covid, we have had people who have stomach aches. I never made the link with BQ.1.1
Dr Jérôme Marty, in Le Parisien
It is therefore above all its infectious potential, likely to cause a powerful epidemic wave in the heart of winter, which is of particular concern. Especially since the epidemic is more and more difficult to “find out”: today, several sub-variants coexist, and are different in the different regions of the world.